I don't think Banshee's at fault here. And probably not Rhythmbox either. Both of them just implement the MPRIS2 interface and let the sound menu take care of that. If anything, it's indicator-sound or unity. I'm marking the Banshee task as invalid.
** Changed in: banshee (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to rhythmbox in Ubuntu. https://bugs.launchpad.net/bugs/806848 Title: unity-panel-service at 100% cpu when opened /w rb without album cover Status in Unity: Confirmed Status in “banshee” package in Ubuntu: Invalid Status in “indicator-sound” package in Ubuntu: Confirmed Status in “rhythmbox” package in Ubuntu: Confirmed Status in “unity” package in Ubuntu: Confirmed Bug description: in oneiric, simply click on the sound indicator, unity-panel-service goes to 100% cpu until the sound menu is closed. unity-services 4.2.0-0ubuntu1 --- Architecture: i386 CompizPlugins: [core,bailer,detection,composite,opengl,compiztoolbox,decor,gnomecompat,commands,vpswitch,resize,snap,mousepoll,regex,move,place,imgpng,session,animation,wall,workarounds,expo,ezoom,staticswitcher,fade,scale,unityshell] DistroRelease: Ubuntu 11.10 NonfreeKernelModules: nvidia Package: unity 4.2.0-0ubuntu3 PackageArchitecture: i386 ProcEnviron: PATH=(custom, user) LANG=en_US.UTF-8 SHELL=/usr/bin/tcsh ProcVersionSignature: Ubuntu 3.0.0-5.6-generic 3.0.0-rc7 Tags: unity-2d oneiric running-unity Uname: Linux 3.0.0-5-generic i686 UpgradeStatus: Upgraded to oneiric on 2011-05-09 (66 days ago) UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare wireshark To manage notifications about this bug go to: https://bugs.launchpad.net/unity/+bug/806848/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp